Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Word Processing”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources
PubMed1999

Left hemisphere activation during processing of morphologically complex word forms in adults.

Functional neuroanatomy of the processing of morphologically complex words was studied by measuring regional brain activity by positron emission tomography (PET) during encoding of auditorily presented inflected versus monomorphemic Finnish nouns. Significant increases of activation occurred particularly in the left inferior posterior frontal lobe, corresponding to Broca's area. This suggests that besides their role in the production of grammatical morphology documented earlier, Broca's area and adjacent regions are important for the input processing of morphologically complex words.

Adult↗
PubMed1998

[Processing of emotional kanji words in the right hemisphere and the effect of handedness on the processing].

Experimental and clinical evidence indicates that the right hemisphere plays a special role in the processing of non-verbal emotional material. The possibility that verbal material may also be similarly processed in the hemisphere was investigated with a reading aloud task, with unilateral tachistoscopic presentation of emotional and non-emotional kanji words. Right-handed subjects, both male and female, participated in Experiment 1 and right and left-handed subjects of both sexes in Experiment 2. Results of Experiment 1 showed that response to non-emotional kanji words were more accurate in the right visual field than in the left, but no difference was found for emotional words. Results of Experiment 2 showed the word-emotionality by visual-field interaction effect on accuracy of both right- and left-handed subjects, but the effect was more pronounced for the right-handed. The results suggest that the right hemisphere processes emotional kanji words just as well as the left.

Emotions↗
PubMed1993

Influence of age and processing stage on visual word recognition.

The authors used a lexical-decision task in 3 different experiments to examine whether age differences in word recognition were consistent across processing stage. In all experiments, word frequency and length were manipulated. In Experiments 1 and 2, encoding difficulty was varied, and in Experiment 3, response selection difficulty was varied. In all 3 experiments, there were no age differences for word frequency. However, in Experiments 1 and 2, older adults showed a larger decrement for encoding. In Experiment 3, age differences were larger when response selection load increased. These results suggest that age differences in word recognition occur because older adults exhibit primarily peripheral-rather than central-processing decrements. The implications of these data for generalized and localized slowing models are discussed.

Adolescent↗
PubMed1996

Effects of perceptual and conceptual processing on memory for words and voice: different patterns for young and old.

In two experiments younger and older adults listened to a list of words presented auditorily by two speakers. The subjects processed each word either perceptually (voice judgements) or conceptually (pleasantness judgements), and were then given memory tasks for the words and the presenting voice. In the word-recognition task the two age groups benefited equally from conceptual as opposed to perceptual processing. In the voice memory task, however, conceptual processing improved performance relative to perceptual processing in the younger subjects (significantly so in Experiment 1), but conceptual processing was associated with decreased performance in the older group (significantly so in Experiment 2). These results suggest that whereas older subjects exhibit a trade-off in memory for item and attribute information, younger subjects exhibit a pattern of support, in which conceptual processing benefits memory for both items and their attributes.

Adult↗
PubMed2006

Concreteness effects in the processing of Chinese words.

The present study examined the relationship between word concreteness and word frequency using event-related potential (ERP) measurements during a lexical decision task. Potential effects of concreteness in the processing of verbs were also examined. ERPs were recorded from 119 scalp electrodes in 23 right-handed participants. The results showed that concrete nouns were associated with a more negative ERP than abstract nouns at 200-300 and 300-500 ms after stimulus onset, regardless of word frequency. Between 300 and 500 ms, concrete nouns and abstract nouns produced differentiated scalp distributions, respectively. In terms of verbs, concreteness only produced small difference in ERP primarily in the central-parietal sites of the left hemisphere.

Adolescent↗
PubMed1989

Context effects in stroop-like word and picture processing.

Presents a series of 6 experiments in which Stroop-like effects were generated by modally pure color-color, picture-picture, and word-word stimuli instead of the usual modally mixed color-word or picture-word stimuli. Naming, reading, and categorization tasks were applied. The Stroop inhibition was preserved with these stimuli but unexpectedly showed a semantic gradient only in the naming and not in the reading task. Word categorizing was slower and more interference prone than picture categorizing. These and other results can be captured by a model with two main assumptions: (a) semantic memory and the lexicon are separate, and (b) words have privileged access to the lexicon, whereas pictures and colors have privileged access to the semantic network. Such a model is developed and put to an initial test.

Adult↗
PubMed2000

Brain potentials associated with recollective processing of spoken words.

The neurocognitive foundations of recollection can be explored by recording event-related potentials (ERPs) from the human brain. In the present study, we monitored brain activity while participants heard a series of words, first in a study phase and again, 1-2 min later, in a test phase, when both priming and recognition were measured. Level of processing at study was manipulated within-subjects via instructions either to visualize the referent of each word (the image task) or to detect the presence of target letters (the letter task). Priming of lexical decision response time was observed but did not differ across study task, whereas recognition was better for image- than for letter-task words. Brain potentials recorded at test revealed a task effect, wherein ERPs were more positive for image- than for letter-task words approximately 600-900 msec after word onset. The task effect was restricted to posterior scalp locations and was interpreted as an indication of visual imagery triggered by spoken words. Given that similar potentials were also elicited at study, we speculate that accurate recognition of words from the image task involved the recapitulation of the visual imagery that was initially engaged during the study phase.

Adolescent↗
PubMed2003

The effects of morphology on the processing of compound words: evidence from naming, lexical decisions and eye fixations.

The use of lexemes during the recognition of spatially unified familiar English compounds was examined in naming, lexical decision and sentence-reading tasks by manipulating beginning and ending lexeme frequencies while controlling overall compound frequencies. All tasks revealed robust ending lexeme frequency effects, with compound processing being more effective when the ending lexeme was a high-frequency word. Beginning lexeme frequency effects were more elusive and dependent on task demands. Eye movements, recorded during sentence reading, also indicated that the effects of ending lexemes occurred after the first fixation during compound viewing. Together, the results suggest either that the ending lexeme is used as an access code to locate the meaning of the full compound word or that its meaning is coactive with the meaning of the full compound.

Adolescent↗
PubMed2005

[Preoperative mapping of speech-eloquent areas with functional magnetic resonance imaging (fMRI): comparison of different task designs].

PURPOSE: Functional magnetic resonance imaging (fMRI) is a well-established, non-invasive method for pre-operative mapping of speech-eloquent areas. This investigation tests three simple paradigms to evaluate speech lateralisation and visualisation of speech-eloquent areas. MATERIALS AND METHODS: 14 healthy volunteers and 16 brain tumour patients were given three tasks: to enumerate months in the correct order (EM), to generate verbs fitting to a given noun (GV) and to generate words fitting to a given alphabetic character (GW). We used a blocked design with 80 measurements which consisted of 4 intervals of speech activation alternating with relaxation periods. The data were analysed on the basis of the general linear model using Brainvoyager(R). The activated clusters in the inferior frontal (Broca) and the posterior temporal (Wernicke) cortex were analysed and the laterality indices calculated. RESULTS: In both groups the paradigms GV and GW activated the Broca's area very robustly. Visualisation of the Wernicke's area was best achieved by the paradigm GV. The paradigm EM did not reliably stimulate either the frontal or the temporal cortex. Frontal lateralisation was best determined by GW and GV, temporal lateralisation by GV. CONCLUSION: The paradigms GV and GW visualise two essential aspects of speech processing: semantic word processing and word production. In a clinical setting with brain tumour patients, both, GV and GW can be used to visualise frontal and temporal speech areas, and to determine speech dominance.

Adult↗
PubMed2005

The influence of encoding strategy on episodic memory and cortical activity in schizophrenia.

BACKGROUND: Recent work suggests that episodic memory deficits in schizophrenia may be related to disturbances of encoding or retrieval. Schizophrenia patients appear to benefit from instruction in episodic memory strategies. We tested the hypothesis that providing effective encoding strategies to schizophrenia patients enhances encoding-related brain activity and recognition performance. METHODS: Seventeen schizophrenia patients and 26 healthy comparison subjects underwent functional magnetic resonance imaging scans while performing incidental encoding tasks of words and faces. Subjects were required to make either deep (abstract/concrete) or shallow (alphabetization) judgments for words and deep (gender) judgments for faces, followed by subsequent recognition tests. RESULTS: Schizophrenia and comparison subjects recognized significantly more words encoded deeply than shallowly, activated regions in inferior frontal cortex (Brodmann area 45/47) typically associated with deep and successful encoding of words, and showed greater left frontal activation for the processing of words compared with faces. However, during deep encoding and material-specific processing (words vs. faces), participants with schizophrenia activated regions not activated by control subjects, including several in prefrontal cortex. CONCLUSIONS: Our findings suggest that a deficit in use of effective strategies influences episodic memory performance in schizophrenia and that abnormalities in functional brain activation persist even when such strategies are applied.

Adult↗
PubMed1995

Spectral responses in the gamma-band: physiological signs of higher cognitive processes?

It has recently been proposed that brain responses in the gamma-range (> 20 Hz) include information about specific cognitive processes in the human brain. Empirical data substantiating this assumption come from EEG and MEG recordings during visual and language processing. For example, 30 Hz activity has been found to be stronger during processing of words than during processing of meaningless but pronounceable pseudo-words. However, it has been reported that power changes in the gamma-band are sometimes artefacts of changes taking place in other frequencies, such as the alpha-band. In this study, we investigated power changes in frequency bands outside the gamma-range and found no evidence that such changes are related to the dynamics in gamma-power distinguishing between words and pseudowords. These results are consistent with the view that gamma-band responses are an indicator of lexical processing and other cognitive processes related to binding of stimulus features into a whole (Gestalt), as proposed by Singer.

Acoustic Stimulation↗
PubMed1998

Semantic processing of spoken words in Alzheimer's disease: an electrophysiological study.

Patients suffering from Alzheimer's disease (AD) have severe difficulties in tasks requiring the use of semantic knowledge. The semantic deficits associated with AD have been extensively studied by using behavioral methods. Many of these studies indicate that AD patients have a general deficit in voluntary access to semantic representations but that the structure of the representations themselves might be preserved. However, several studies also provide evidence that to some extent semantic representations in AD may in fact be degraded. Recently, a few studies have utilized event-related brain potentials (ERPs) that are sensitive to semantic factors in order to investigate the electrophysiological correlates of the semantic impairment in AD. Interest has focused on the N400 component, which is known to reflect the on-line semantic processing of linguistic and pictorial stimuli. The results from studies of N400 changes in AD remain somewhat controversial: Some studies report normal or enlarged N400 components in AD, whereas others report diminished ones. One issue not reported in previous studies is whether word-elicited ERPs other than N400 remain normal in AD. In the present study our aim was to find out whether the ERP waveforms N1, P2, N400, and Late Positive Component (LPC) to semantically congruous and incongruous spoken words are abnormal in AD and whether such abnormalities specifically reflect deficiencies in semantic activation in AD. Auditory ERPs from 20 scalp sites to semantically congruous and incongruous final words in spoken sentences were recorded from 17 healthy elderly adults and 9 AD patients. The early ERP waveforms N1 and P2 were relatively normal for the AD patients, but the N400 and LPC effects (amplitude difference between congruous and incongruous conditions) were significantly reduced. We interpret the present results as showing that semantic-conceptual activation and other high-level integration processes are defective in AD. However, a word congruity effect earlier than N400 (phonological mismatch negativity), reflecting lexical selection processes, is at least to some extent preserved in AD.

Aged↗
PubMed1998

The processing of compound words: a study in aphasia.

The naming difficulties of an aphasic patient (MB) are almost exclusively confined to compound words. The paraphasias in response to compounds always reflect the compound structure of the targets. Frequent semantically adequate substitution errors suggest the separate processing of single components at the lemma level. MB's specific difficulties probably arise when two lemmas are defined by one lexical entry, as we suggest for compounds. The compound structure, as well as the positions of the single lemmas within the compound, would be specified before lemmas are accessed. The lack of a positional effect in substitution errors suggests a parallel activation of the two components.

Adult↗
PubMed1999

Sex differences in phonological processes: speeded matching and word reading.

Sex differences in phonological processing were investigated in four experiments. Two experiments required college students to decide whether two five-letter strings matched. Same-case (AA) pairs of letter strings could be matched using physical features, whereas mixed-case (Aa) pairs of letter strings required the mediation of a speech-based code (letter name) for the comparison. Women were significantly faster than men when the comparisons required the speech-based codes. In another experiment, college students read lists of words and lists of pseudohomophones to determine whether there was a sex difference in the computation of phonology for unfamiliar words (assembled phonology). In a final experiment, students read lists of words with phonologically inconsistent spelling patterns to determine whether there was a sex difference in accessing pronunciations of familiar words (addressed phonology). Women were more proficient than men under both of these conditions. Results were interpreted in terms of a female advantage in both prelexical and lexical processing, an advantage that may stem from a sex difference in the quality of the phonological representations.

Adult↗
PubMed2004

Interaction between phonological and grammatical processing in single word production in Kiswahili.

Grammatical priming of picture naming was investigated in Kiswahili, which has a complex grammatical noun class system (a system like grammatical gender), with up to 15 noun classes that have obligatory agreements on adjectives, verbs, pronouns and other parts of speech. Participants heard a grammatically agreeing (concordant), nonagreeing (discordant) or neutral prime before seeing a picture of a common object and being asked to name the object. Priming was found, with naming following concordant primes being faster than naming following the neutral prime ('say'). However, more interestingly, effects were found such that where two noun classes share a prefix, the grammatical prime from each of these two noun classes also primed words that have the same prefix but are not in the same noun class, and hence for which the prime was not grammatical. It is concluded that the prime appears to be facilitating the phonological form of the prefix rather than the syntacto-semantic group of words that are known as a noun class, and that the phonological form associated with a grammatical entity may be more significant in its processing than has previously been supposed.

Adolescent↗
PubMedDate not supplied

Speech to infants as hyperspeech: knowledge-driven processes in early word recognition.

The intelligibility of a word in continuous speech depends on the clarity of the word and on linguistic and nonlinguistic contextual information available to the listener. Despite limited knowledge of language and the world, infants in the first 2 years are already beginning to make use of contextual information in processing speech. Adults interacting with infants tend to modify their speech in ways that serve to maximize predictability for the immature listener by highlighting focussed words and using frequent repetition and formulaic utterances. Infant-directed speech is viewed as a form of 'hyperspeech' which facilities comprehension, not by modifying phonetic properties of individual words but rather by providing contextual support on perceptual levels accessible to infants even in the earliest stages of language learning.

Adult↗